A supercell thunderstorm developed over northern Campbell County and moved southeastward across Crook County. The storm produced very large hail across western Crook County, which caused significant damage in the New Haven and Hulett areas. The storm also spawned a large tornado over the Bear Lodge Mountains north of Sundance.

Event Narrative

A large tornado touched down west of Cook Lake and tracked east-southeastward across the Bear Lodge Mountains, dissipating west of Wyoming Highway 111. The tornado downed about 4000 acres of Ponderosa pine trees, destroyed two metal shop buildings and a large barn at a ranch, and severely damaged a house and mobile home. Two people in the residences received very minor injuries.